Oracle database links

I can't get the database links to work. Just how do you create a database link? If I have two machines on the network named PRIMARY and BACKUP, I create a database on each with a SID of MYDB and a database name (DB_NAME) of MYDATABASE, and I use SQL*NET to create database aliases of MYDB_ON_PRIMARY and MYDB_ON_BACKUP on each machine so that I can access both databases from both machines, what should my CREATE DATABASE LINK command look like so I can access tables in MYDB_ON_BACKUP from MYDB_ON_PRIMARY? I've tried CREAT PUBLIC DATABASE LINK LINK_TO_BACKUP USING 'MYDB_ON_BACKUP' from the PRIMARY machine while logged into the database MYDB_ON_PRIMARY. But when I try to select anything from the table using SELECT * FROM TABLE_at_LINK_TO_BACKUP it fails. Both machines are in the same domain and I can CONNECT INTERNAL/PASSWORD_at_MYDB_ON_PRIMARY and CONNECT INTERNAL/PASSWORD_at_MYDB_ON_BACKUP from both machines, so I know both databases are OK. Received on Tue Jun 18 1996 - 00:00:00 CEST